Nonvolatile memory devices having multiple-layer structures have been devised in order to improve the integration degree. In such nonvolatile memory devices, the number of photolithography processes tends to increase. In each photolithography process, alignment marks are used to make alignment between a mask and an underlayer pattern. If the marks used in each photolithography process are formed in a region different from the other photolithography processes, the area of the mark region is increased. As a result, the karf area (dicing area) of a wafer is increased.